Soyuz 15

Soyuz 15

Mission type	Docking with Salyut 3
Operator	Experimental Design Bureau (OKB-1)
COSPAR ID	1974-067A
SATCAT no.	07421
Mission duration	2 days 12 minutes 11 seconds
Orbits completed	32
Spacecraft properties
Spacecraft	Soyuz 7K-T No.4
Spacecraft type	Soyuz 7K-T/A9
Manufacturer	Experimental Design Bureau (OKB-1)
Launch mass	6570 kg [1]
Landing mass	1200 kg
Crew
Crew size	2
Members	Gennady Sarafanov Lev Dyomin
Callsign	Дунай (Dunay - "Danube")
Start of mission
Launch date	26 August 1974, 19:58:05 UTC
Rocket	Soyuz
Launch site	Baikonur, Site 1/5[2]
Contractor	Experimental Design Bureau (OKB-1)
End of mission
Landing date	28 August 1974, 20:10:16 UTC
Landing site	48 km at the southwest of Tselinograd
Orbital parameters
Reference system	Geocentric orbit[3]
Regime	Low Earth orbit
Perigee altitude	254.0 km
Apogee altitude	275.0 km
Inclination	51.60°
Period	89.60 minutes
Salyut program insignia Soyuz programme ← Soyuz 14 Soyuz 16 →

Soyuz 15 (Russian: Союз 15, Union 15) was an August 1974 crewed space flight which was to have been the second mission to the Soviet Union's Salyut 3 space station with presumably military objectives.^[4]

Launched 26 August 1974, the Soyuz spacecraft arrived at the station, but cosmonauts Gennady Sarafanov and Lev Dyomin were unable to dock because the electronics in the Igla docking system malfunctioned. Without sufficient fuel for prolonged attempts at manual docking, the mission had to be abandoned. The cosmonauts powered down all nonessential systems in the Soyuz and waited until the next day for reentry.^[5] The crew landed 28 August 1974. Analysis of the launch window was cited by observers for concluding a flight of 19 to 29 days had been planned.^[5]

In the event of the failure, official TASS statements merely claimed that the mission was intended to practice docking maneuvers with the Salyut 3 station.^[4] They also said that a new automatic docking system was tested which would be used on future Progress transport craft.^[5]

The failed mission exposed a number of serious design flaws in the Soyuz 7K-T spacecraft, namely its lack of reserve propellant and electrical power for repeated docking attempts. In addition, the Igla docking system was found to be in major need of improvement. Since it was impossible to carry out these changes before Salyut 3 finished its operating lifespan, they had to wait for future space stations. The backup spacecraft for the Soyuz 15 mission was placed in storage and later flown as Soyuz 20 despite being past its intended shelf life.

Crew

Backup crew

Reserve crew

Mission parameters

• Mass: 6,570 kg (14,480 lb) ^[1]
• Perigee: 254.0 km (157.8 mi) ^[3]
• Apogee: 275.0 km (170.9 mi)
• Inclination: 51.60°
• Period: 89.60 minutes

References

• v
• t
• e

Soyuz programme

• List of Soyuz missions
• List of Soviet human spaceflight missions
• List of Russian human spaceflight missions

Main topics

• Soyuz (rocket family)
• Soyuz (spacecraft)
• Baikonur Cosmodrome
  • Site 1/5
  • Site 31/6
• Soyuz abort modes
• Cosmonaut ranks and positions

Past missions
(by spacecraft type)

Soyuz 7K-OK (1966–1970)	Kosmos 133† Soyuz 7K-OK No.1† (uncrewed) Kosmos 140 Soyuz 1† Kosmos 186 188 212 213 238 Soyuz 2 (uncrewed) 3 4 5 6 7 8 9
Soyuz 7K-L1 (1967–1970) (Zond lunar programme)	Kosmos 146 154† Zond 1967A† 1967B† Zond 4 1968A† 1968B† 5 6 1969A† Zond-M 1† M 2† Zond 7 8 9 10
Soyuz 7K-L1E (1969–1970)	Soyuz 7K-L1E No.1† Kosmos 382
Soyuz 7K-LOK (1971–1972)	Soyuz 7K-LOK No.1† No.2†
Soyuz 7K-OKS (1971)	Soyuz 10† 11†
Soyuz 7K-T (1972–1981)	Kosmos 496 573 Soyuz 12 Kosmos 613 Soyuz 13 Kosmos 656 Soyuz 14 15† 17 18a† 18 20 (uncrewed) 21 23† 24 25† 26 27 28 29 30 31 32 (uncrewed landing) 33† 34 (uncrewed launch) 35 36 37 38 39 40
Soyuz 7K-TM (1974–1976)	Kosmos 638 672 Soyuz 16 19 (Apollo–Soyuz) 22
Soyuz 7K-S (1974–1976)	Kosmos 670 772† 869†
Soyuz-T (1978–1986)	Kosmos 1001† 1074 Soyuz T-1 (uncrewed) T-2 T-3 T-4 T-5 T-6 T-7 T-8† T-9 T-10a† T-10 T-11 T-12 T-13 T-14 T-15
Soyuz-TM (1986–2002)	Soyuz TM-1 (uncrewed) TM-2 TM-3 TM-4 TM-5 TM-6 TM-7 TM-8 TM-9 TM-10 TM-11 TM-12 TM-13 TM-14 TM-15 TM-16 TM-17 TM-18 TM-19 TM-20 TM-21 TM-22 TM-23 TM-24 TM-25 TM-26 TM-27 TM-28 TM-29 TM-30 TM-31 TM-32 TM-33 TM-34
Soyuz-TMA (2002–2012)	Soyuz TMA-1 TMA-2 TMA-3 TMA-4 TMA-5 TMA-6 TMA-7 TMA-8 TMA-9 TMA-10 TMA-11 TMA-12 TMA-13 TMA-14 TMA-15 TMA-16 TMA-17 TMA-18 TMA-19 TMA-20 TMA-21 TMA-22
Soyuz-TMA-M (2010–2016)	Soyuz TMA-01M TMA-02M TMA-03M TMA-04M TMA-05M TMA-06M TMA-07M TMA-08M TMA-09M TMA-10M TMA-11M TMA-12M TMA-13M TMA-14M TMA-15M TMA-16M TMA-17M TMA-18M TMA-19M TMA-20M
Soyuz MS (2016–present)	Soyuz MS-01 MS-02 MS-03 MS-04 MS-05 MS-06 MS-07 MS-08 MS-09 MS-10† MS-11 MS-12 MS-13 MS-14 (uncrewed test flight) MS-15 MS-16 MS-17 MS-18 MS-19 MS-20 MS-21 MS-22 (uncrewed landing) MS-23 (uncrewed launch) MS-24

Current missions

• MS-25

Future missions

• 2024
  • MS-26

Uncrewed missions are designated as Kosmos instead of Soyuz; exceptions are noted "(uncrewed)".
The † sign designates failed missions. Italics designates cancelled missions.